Background: Coronary collateral circulation (CCC) is linked to myocardial remodeling severity in patients with chronic ischaemic heart disease (IHD). However its effect on left ventricular reverse remodeling (LVRR) in patients with chronic IHD underwent coronary artery bypass surgery (CABG) has never been reported. Purpose of this study was to investigate the effect of CCC grade on the LVRR event in patients with chronic IHD underwent CABG. Methods: This prospective cohort study was performed in patients with chronic IHD underwent CABG. The CCC was classified using Rentrop collateral score, i.e low CCC grade (Rentrop score 0 and 1) and high CCC grade (Rentrop score 2 and 3).  LVRR event was defined as a reduction in left ventricular end systolic volume (LVESV) of 10% or more, measured by a 3D echocardiography at 1.5 months post CABG compared to the baseline before CABG. Results: A total of 22 patients (81.8% male) with mean of age 58.6 years old were enrolled. LVRR occurred in 50% patients. LVRR event was significantly higher in the patients with high CCC grade than the low CCC grade patients (p=0.009). The high CCC grade increased LVRR event independently (odds ratio=26.67; relative risk=6.93). Conclusions: High coronary collateral circulation may increase left ventricular reverse remodeling event in patients with chronic ischemic heart disease underwent coronary artery bypass surgery. Keywords: coronary collateral circulation; left ventricular reverse remodeling; chronic ischaemic heart disease; coronary artery bypass surgery; 3D echocardiography.

Background: Double coronary culprit lesions in ST-segment elevation myocardial infarction (STEMI) is uncommon. Despite successful primary percutaneous coronary intervention (PPCI) in all culprit lesions, the clinical outcome remains unfavorable and the possible factors for the outcome are not fully understood.Cases Presentation: We reported four cases of double culprit lesions STEMI underwent PPCI. Patient A, a 62 y.o. male with extensive anterior-inferior STEMI, had total occlusion (TO) at both proximal left anterior descending (LAD) and mid right coronary artery (RCA). Patient B, a 42 y.o. male with extensive anterior-inferior STEMI, had subtotal occlusion (STO) at proximal RCA and TO at proximal LAD. Both of them had RBBB ECG pattern. Patient C, a 67 y.o. male with inferior STEMI had 90% thrombus occlusion at proximal–mid LAD and TO at proximal RCA. Patient D, a 65 y.o. male with anteroseptal STEMI, had STO at proximal LAD and 80% thrombus occlusion at mid left circumflex. The cardiomyocyte infarction biomarkers increased in all patients. Although all of them underwent successful PPCI in all of culprit lesions, they suffered from acute heart failure and two of them experienced recurrent ventricular arrhythmia episodes. One of them (patient A) died two days post PPCI. He was only patient who suffering from total occlusion in LAD and RCA with TIMI thrombus 5 and experienced a total atrioventricular block post-PPCI.Conclusion: STEMI with coronary double culprits have severe clinical outcome, regardless of the successful PCI. The degree of coronary occlusions might be linked to the patient clinical outcome.